Question

Two sides of a triangle have lengths of 12m and 15m the angles between them are increasing at a rate of 2 degrees per minute.How fast is the length of the third side increasing when the angle between the sides of fixed length is 60 degrees?

Please help I am confused.

Answer 1

@ajprincess @hartnn please help

Answer 2

u need cosine rule here, know what is it ?

Answer 3

no

Answer 4

from cosine-rule, we have
\(\huge c^2=a^2+b^2-2ab\cos\theta\)

Answer 5

okay

Answer 6

Given , a,b,\(\frac{d}{dt}\theta\)

Answer 7

and \(\theta\)

Answer 8

u could identify all 4 of these values, right ?

Answer 9

im not sure

Answer 10

two sides, a and b are given as ....?
the rate of angle change per minute = \(\frac{d}{dt}\theta\)= ....?
and the angle itself is given as \(\theta=....degrees?\)

Answer 11

okay

Answer 12

so tell me all 4 values, first.

Answer 13

next i need to know whether u can differentiate?

Answer 14

im confused

Answer 15

on which value ?

Answer 16

you showed me only 3

Answer 17

2 sides, a and b are 2 values.

Answer 18

okay

Answer 19

never mind i already got the answer thanks anyway